XBMC always outputs LPCM
#16
If I uncheck Multichannel-LPCM, I do get the PLII light, but the sound is horrible on AAC recordings as they are apparently being sent out as mono with this setting. Do you play any videos with AAC?

I don't even have an "AAC compatible receiver" option. Weird that it's on 12.1 but not the latest nightly. The only passthough options I have are:
-Dolby Digital (AC3) capable receiver
-DTS capable receiver
-Multichannel LPCM capable receiver
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#17
i have tried your setting

I can confirm that playing 2.0 aac with lpcm turned on switches audio midi setup to 8 channel.

Disabling lpcm and having audio midi setup set to 2.0 aswell as having xbmc set to 2.0 works for me with current nightly builds (i get stereo sound and can switch the amp to pl2).

AAC passthrough was removed as there is no receiver on the marked which really can decode aac. There is missleading info on that all around the web - but our audio gurus really confirmed that aac passthrough is a stupid marketing gag - so we removed the option ...
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#18
Ohhh and btw switching to 8 channel output when using LPCM is by spec. Its a thing of apple itslef that they really send out 7.1 even if only 2 channels are passed to it. Nothing we can change about that afais...
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#19
OK, I tried unchecking multichannel LPCM while leaving the output on HDMI instead of analog, and I'm not getting mono now. I get 2.0 with PLII on my receiver. Don't know what happened when I tried this before, but clearly this is a superior approach than using analog 2.0 output from XBMC as it does get passthrough for AC3 files.

I still think that switching to 8 channels is the cause of the 1h2m8s bug, even if apple recommends it, but this is the wrong thread for that, and turning off multichannel LPCM is a good workaround anyway.
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#20
Next nightly will have a change where it only sets 8 channels in audio midi setup if the stream has more then 2.0 channels. This should fix your AAC2.0 DPII thing even when having LPCM turned on. Though the 1h2min bug is not limitied to LPCM scenarios (as of the multiple reports with different setups - it clearly happens with nearly all possible constellations on some macs) - so this is very unlikly to fix anything else in that region.
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#21
Memphiz: Thanks, I just saw this while posting in the 1h2m8s thread. I'll try it out tomorrow. I have several files that have been reliably stuttering at 46 min. I'll have to look for a multichannel AAC file to test also. Even if it doesn't fix the stuttering it is an improvement for the stereo AAC files.
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#22
you will experience wrong channel mapping when using multichanel aac most likely - be warned...
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#23
(2013-04-26, 22:04)Memphiz Wrote:
(2013-04-26, 19:10)PalleO Wrote: The thing I fail to understand is how you Mac developers can write a new Audioengine, but can't fix the errors following? No intention in creating a hate for you guys, I think you're doing a great job! :-)
As far as I know, the OS X version worked much better with audio in the earlier versions of Xbmc. So how come you didn't stick to the original audio code?

I really hope that it will get fixed. I love xbmc and with my setup, I can't see how I should be able to replace my Mac with another platform.

Thats pretty easy to understand. The guys who did the audio engine (incl. the dev doing the osx part) just quit doing that stuff. Its as easy as that. And for us outstanding devs there is not much motivation on trying to clean a mess which we don't understand. Shit happens.

Arh, I see :-) Thanx for the explanation, Memphiz :-) Pretty logic now
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#24
(2013-04-27, 09:12)Memphiz Wrote: you will experience wrong channel mapping when using multichanel aac most likely - be warned...

Is there a different codec I should try that will handle multichannel audio but be properly converted to multichannel-LPCM by XBMC?
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#25
its codec independend - if it is not passthrough but lpcm - channelmapping is hit and miss...
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#26
Would the LPCM decoding receiver be responsible for the channel mapping?
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#27
I found a good multichannel sound test file here, in this thread. It has separate audio tracks in flac, aac and dolby in 5.1 an 7.1. Only the dolby 5.1 (AC3) file uses passthrough on my setup. The others are all multichannel LPCM. There are some subtle differences between the different audio tracks, but they all seem to be in close to the right place. I can't tell much more on my soundbar, but they certainly don't sound obviously wrong in any way (Like left instead of right or non-symmetric).

There is a reproducible difference between the codecs in that aac 7.1 always sounds the same and is always different in the same way from flac 7.1, but this could be due to how the True-HD was transcoded rather than something XBMC is doing.
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#28
I've been wondering for a while why in Mountain Lion audio midi setup won't stay at 2ch, but changes to 8ch and won't change back automatically to 2ch. This sort of explains it.

In Snow Leopard it either does not change to 8ch at all, or it changes to 8ch and returns back to 2ch when needed, i don't have this issue with SL.
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#29
It changes back fine for me on mountain lion.

Beside that i have disable AC3 and DTS on my setup and only activated LPCM ... playing ac3 and dts 5.1 sound got the correct channel mapping for me. I have only one testfile AAC 5.1 which might just be screwed - it plays with wrong channel mapping. Will try the tests you posted if i get some time.
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#30
Thanks for all your replies. I actually solved the problem yesterday by changing the settings in the OSX MIDI setup (i had never seen these settings before, so I didn't know you could change speaker config). By disabling LPCM capable receiver and enabling DTS/DD, all 2.0 sources are sent as 2.0 stream to the surround processor for DPL-processing and 5.1 encoded videos are bitstreamed untouched to the processor for decoding. This is exactly what I wanted.
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